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1.
Soft Matter ; 20(12): 2767-2776, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38441577

RESUMEN

Magnetic nanomaterials are gaining interest for their many applications in technological areas from information science and computing to next-generation quantum energy materials. While magnetic materials have historically been nanostructured through techniques such as lithography and molecular beam epitaxy, there has recently been growing interest in using soft matter self-assembly. In this work, a triblock terpolymer, poly(isoprene-block-styrene-block-ethylene oxide) (ISO), is used as a structure directing agent for aluminosilicate sol nanoparticles and magnetic material precursors to generate organic-inorganic bulk hybrid films with co-continuous morphology. After thermal processing into mesoporous materials, results from a combination of small angle X-ray scattering (SAXS) and scanning electron microscopy (SEM) are consistent with the double gyroid morphology. Nitrogen sorption measurements reveal a type IV isotherm with H1 hysteresis, and yield a specific surface area of around 200 m2 g-1 and an average pore size of 23 nm. The magnetization of the mesostructured material as a function of applied field shows magnetic hysteresis and coercivity at 300 K and 10 K. Comparison of magnetic measurements between the mesoporous gyroid and an unstructured bulk magnetic material, derived from the identical inorganic precursors, reveals the structured material exhibits a coercivity of 250 Oe, opposed to 148 Oe for the unstructured at 10 K, and presence of remnant magnetic moment not conventionally found in bulk hematite; both of these properties are attributed to the mesostructure. This scalable route to mesoporous magnetic materials with co-continuous morphologies from block copolymer self-assembly may provide a pathway to advanced magnetic nanomaterials with a range of potential applications.

2.
JAMA Netw Open ; 6(6): e2320527, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37389875

RESUMEN

Importance: Preoperative high-intensity interval training (HIIT) is associated with improved cardiorespiratory fitness (CRF) and may improve surgical outcomes. Objective: To summarize data from studies comparing the association of preoperative HIIT vs standard hospital care with preoperative CRF and postoperative outcomes. Data Sources: Data sources included Medline, Embase, Cochrane Central Register of Controlled Trials Library, and Scopus databases with no language constraints, including abstracts and articles published before May 2023. Study Selection: The databases were searched for randomized clinical trials and prospective cohort studies with HIIT protocols in adult patients undergoing major surgery. Thirty-four of 589 screened studies met initial selection criteria. Data Extraction and Synthesis: A meta-analysis was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Data were extracted by multiple independent observers and pooled in a random-effects model. Main Outcomes and Measures: The primary outcome was change in CRF, as measured by either peak oxygen consumption (V̇o2 peak) or 6-Minute Walk Test (6MWT) distance. Secondary outcomes included postoperative complications; hospital length of stay (LOS); and changes in quality of life, anaerobic threshold, and peak power output. Results: Twelve eligible studies including 832 patients were identified. Pooled results indicated several positive associations for HIIT when compared with standard care either on CRF (V̇o2 peak, 6MWT, anaerobic threshold, or peak power output) or postoperative outcomes (complications, LOS, quality of life), although there was significant heterogeneity in study results. In 8 studies including 627 patients, there was moderate-quality evidence of significant improvement in V̇o2 peak (cumulative mean difference, 2.59 mL/kg/min; 95% CI, 1.52-3.65 mL/kg/min; P < .001). In 8 studies including 770 patients, there was moderate-quality evidence of a significant reduction in complications (odds ratio, 0.44; 95% CI, 0.32-0.60; P < .001). There was no evidence that HIIT differed from standard care in hospital LOS (cumulative mean difference, -3.06 days; 95% CI, -6.41 to 0.29 days; P = .07). The analysis showed a high degree of heterogeneity in study outcomes and an overall low risk of bias. Conclusions and Relevance: The results of this meta-analysis suggest that preoperative HIIT may be beneficial for surgical populations through the improvement of exercise capacity and reduced postoperative complications. These findings support including HIIT in prehabilitation programs before major surgery. The high degree of heterogeneity in both exercise protocols and study results supports the need for further prospective, well-designed studies.


Asunto(s)
Capacidad Cardiovascular , Entrenamiento de Intervalos de Alta Intensidad , Humanos , Adulto , Estudios Prospectivos , Calidad de Vida , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control
3.
Adv Mater ; 35(5): e2203908, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35863756

RESUMEN

The field of quantum materials has experienced rapid growth over the past decade, driven by exciting new discoveries with immense transformative potential. Traditional synthetic methods to quantum materials have, however, limited the exploration of architectural control beyond the atomic scale. By contrast, soft matter self-assembly can be used to tailor material structure over a large range of length scales, with a vast array of possible form factors, promising emerging quantum material properties at the mesoscale. This review explores opportunities for soft matter science to impact the synthesis of quantum materials with advanced properties. Existing work at the interface of these two fields is highlighted, and perspectives are provided on possible future directions by discussing the potential benefits and challenges which can arise from their bridging.

4.
J Hazard Mater ; 361: 305-311, 2019 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-30216859

RESUMEN

A water-based silsesquioxane (POSS)-containing polymer, POSS-PAA, was synthesized by using octavinyl-POSS (V-POSS) and acrylic acid (AA) via interfacial polymerization. The TEM of POSS-PAA showed that the polymer formed a core-shell structure in aqueous solution and was well-dispersed. The star-shaped POSS-PAA and linear PAA were both tanned with 3.5% chromium tanning agent, and leather hide was tanned with 3.5% chromium tanning agent as a control. The results showed that the shrinkage temperature of wet-blue leather treated by POSS-PAA was increased by 3.5 °C than that of the control. The thickening rate of the POSS-PAA treated wet-blue leather samples was increased by 21% and 96% than the linear PAA-treated leather and the control leather, respectively. The EDS results suggested that the POSS-PAA pre-treated leather had a higher chromium content than the others, and the chromium distribution from the leather flesh side to the grain side was uniform. Moreover, the Cr2O3 content in both the POSS-PAA and the PAA pre-treated tanning waste water was reduced by about 50%, compared to the control waste. The COD and BOD of the POSS-PAA pre-tanning waste were decreased compared to the others. Therefore, POSS-PAA appeared to be promising for promoting the development of cleaner leather production.

5.
Adv Mater ; 29(24)2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28429495

RESUMEN

The wrinkle dynamics (such as reversibility and stability) of human skin are affected by the external stimuli, as well as the skin's structure and mechanical properties. Inspired by these tunable responses, three types of moisture-responsive wrinkle dynamics are achieved, for the first time, through a single film-substrate system. These dynamics include: (1) completely reversible wrinkles formation; (2) irreversible wrinkles formation I: the initially formed wrinkles can be permanently erased and never reappear; and (3) irreversible wrinkles formation II: once the wrinkles form, they can no longer be erased. The key to success is to control the stiffness and thickness ratios of the film and the substrate, and tailor the crosslink degree/gradient of the film to allow for moisture-dependent changes of modulus and swelling degree. These unique responsive dynamics motivate the invention of a series of optical devices triggered by moisture, including anticounterfeit tabs, encryption devices, water indicators, light diffusors, and antiglare films. This study also paves the road for further understanding of the skin wrinkling dynamics and manipulation.

6.
Ann Vasc Surg ; 24(8): 1135.e13-8, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20685073

RESUMEN

Persistent sciatic artery (PSA) is an exceptionally rare embryological vascular anomaly with a reported incidence, based on angiographic series, of between 0.01 and 0.05%. We report a case of a patient with bilateral PSAs and a unilateral 12-cm aneurysm arising from the left PSA. As with our case, most PSAs are among the dominant arteries that supply blood to the lower limb with aneurysm formation occurring in up to 40% of cases. The femoral artery is often hypoplastic. Presentation usually includes symptoms and signs of an enlarged buttock mass, sciatic nerve compression, and distal limb ischemia. An interposition inlay graft is the preferred method of surgical repair. Dissection of the aneurysm is not recommended because of risk of damage to the sciatic artery. Endovascular stent placement is an accepted method of repair but does not deal with any local symptoms of the expanding aneurysm.


Asunto(s)
Aneurisma/complicaciones , Extremidad Inferior/irrigación sanguínea , Malformaciones Vasculares/complicaciones , Adulto , Aneurisma/diagnóstico por imagen , Aneurisma/cirugía , Arterias/anomalías , Arterias/cirugía , Femenino , Humanos , Angiografía por Resonancia Magnética , Radiografía , Vena Safena/trasplante , Resultado del Tratamiento , Injerto Vascular , Malformaciones Vasculares/diagnóstico por imagen , Malformaciones Vasculares/cirugía
7.
Surg Today ; 38(6): 541-4, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18516535

RESUMEN

Angiosarcoma of the femoral artery is an extremely rare malignant vascular tumor. The initial diagnosis is difficult to establish and distal metastasis can sometimes be the only presenting symptom. In this paper, we report the case of a 54-year-old man who presented with multiple painful necrotic lesions over the right foot secondary to an intimal angiosarcoma of the right common femoral artery.


Asunto(s)
Arteria Femoral , Hemangiosarcoma/patología , Células Neoplásicas Circulantes/patología , Neoplasias Vasculares/patología , Humanos , Masculino , Persona de Mediana Edad , Dedos del Pie
8.
Vasc Endovascular Surg ; 41(5): 460-2, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17942864

RESUMEN

We report the case of a 76-year-old man of the Jehovah's Witness faith who had a giant abdominal aortoiliac aneurysm that was successfully operated on using an aortoiliac Y-graft bypass technique, without the use of stored allogenic blood. Cell saver technique and recombinant human erythropoietin (epoetin beta) were used during the perioperative period. The patient had good postoperative care with a multidisciplinary approach.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Pérdida de Sangre Quirúrgica/prevención & control , Transfusión de Sangre Autóloga , Implantación de Prótesis Vascular , Aneurisma Ilíaco/cirugía , Testigos de Jehová , Religión y Medicina , Anciano , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Transfusión de Sangre Autóloga/instrumentación , Epoetina alfa , Eritropoyetina/uso terapéutico , Hematínicos/uso terapéutico , Humanos , Aneurisma Ilíaco/diagnóstico por imagen , Masculino , Proteínas Recombinantes , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
9.
Knee ; 9(4): 349-51, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12424047

RESUMEN

Arterial complications following Total Knee Replacement are uncommon. We present a case of false aneurysm of the superior lateral geniculate artery presenting in the immediate postoperative period with continued bleeding from the surgical wound. This is the first case of false aneurysm of this vessel described following Total Knee Replacement. A method of treatment is outlined. Early consultation with vascular surgery colleagues is recommended to prevent delayed diagnosis of serious vascular complications.


Asunto(s)
Aneurisma Falso/etiología , Artroplastia de Reemplazo de Rodilla/efectos adversos , Rodilla/irrigación sanguínea , Anciano , Aneurisma Falso/cirugía , Arterias/lesiones , Arterias/cirugía , Humanos , Masculino
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